Use the Following Data for the Next Questions

question 7

Essay

Use the following data for the next questions. Biologists, researching the effects
of adding limestone sand as buffer for acid rain effects in streams, monitored the
pH levels of two streams each month for 36 months. The first stream had a mean
pH level of 6.8 with a standard deviation of 2.3. The control stream had a mean pH
level of 9.2 with a standard deviation of 1.5. Assume a .05 significance level for
testing the claim that the mean pH of the first stream was less (more acidic) than
the mean pH of the control stream. Also, assume the two samples are independent
simple random samples selected from normally distributed populations.
-Use a .05 significance level and the traditional or P-value method for hypothesis testing the claim that the pH level in the first stream has a standard deviation different from that in the second stream. State a conclusion about the null hypothesis and a final conclusion that addresses the original claim.

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Definitions:

Direct Labor-hours

The total hours worked by employees who are directly involved in the manufacturing or production process of goods.

Predetermined Overhead Rate

A rate used to allocate manufacturing overhead costs to products, calculated based on estimated costs and activity levels.

Direct Labor-hours

The total hours worked by employees that can be directly associated with the production of goods or services.

Manufacturing Overhead

All indirect costs related to the production process, including salaries, maintenance, and utilities, not directly attributable to specific units produced.